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121.
phbB,phbC基因克隆,序列分析及植物表达载体的构建 总被引:11,自引:0,他引:11
利用聚合酶链式反应技术,从真养产碱杆菌Alcaligenes eutrophus H16染色体DNA中的主增并克隆了调控聚-β-羧基丁酸生物合成的两个关键酶基因;依赖NADPH的乙酰乙酰CoA还原酶基因和PHB合成酶基因。限制性内切酶图谱和核苷酸序列分析证实了克隆结果,并表明所克隆的基因与国外报道的有很高的同源性。 相似文献
122.
Hae-Chul Park Kyung-Jun Lim Jin-Seo Park Yong-Hyun Lee Tae-Lin Huh 《Biotechnology Techniques》1995,9(1):31-34
Summary A strain of Alcaligenes eutrophus producing poly--hydroxybutyric acid was successfully transformed by the electroporation. The plasmid used was a broad host range plasmid pKT230 conferring kanamycin resistance. The optimum yield of transformant was 0.8×102/g DNA when 50 l competent cells at 1010/ml were pulsed by 11.5 kV/cm for 5 ms with 1 g DNA. Plasmid DNA in the A. eutrophus transformant was stably maintained as a monomeric structure. 相似文献
123.
124.
Characterization of translation products of the polyadenylated RNA of free and membrane-bound polyribosomes of rat forebrain. 总被引:4,自引:2,他引:2
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Poly(A)+ RNA (polyadenylated RNA) isolated from membrane-bound and free polyribosomes was translated in reticulocyte lysates, and the products were analysed by two-dimensional gel electrophoresis. Several translation products were specific to membrane-bound polyribosomal mRNA, including polypeptides of 47kDa, 35kDa and 21 kDa, whereas others (e.g. of 37 kDa, 17 kDa and 14 kDa) were specific to free polyribosomal mRNA. Although many products were common to both mRNA species, cross-contamination could be ruled out on the basis of the presence of these and other specific products. The common products included a 68 kDa microtubule-associated protein, tubulin, actin, the brain form of creatine kinase, neuron-specific enolase and protein 14-3-3 and calmodulin, all of which were identified on the basis of two-dimensional gel and peptide analyses. The 35 kDa protein product of membrane-specific mRNA was co-translationally processed in vitro by microsomal membranes, resulting in its cleavage to 33 kDa (and partial glycosylation). The 33 kDa processed protein (but not the 35 kDa precursor) was integrated into both dog pancreas and rat brain microsomal membranes. The occurrence of the enzymes and calmodulin as products of membrane-bound polyribosomal mRNA is discussed in the light of their presence on rat brain synaptic plasma membranes [Lim, Hall, Leung, Mahadevan & Whatley (1983) J. Neurochem. 41, 1177-1182] and their existence in a specific component of axonal flow. It is suggested that some of these translation products of the rough endoplasmic reticulum may represent proteins destined for the plasma membrane. However, the identity and location of the 35 kDa membrane-specific product (or its processed form) still remain unestablished. 相似文献
125.
126.
A collection of dicroceolid flukes from rats, squirrels and Tupaia in Malaysia is found to be morphologically heterogeneous. Cluster analysis on the basis of three selected body ratios distinguishes two major types comprising highly diverse Skrjabinus from rats, and homogenous Zonorchis from callosciurid squirrels. Tupaia harbours flukes of both genera. Analysis of variance of flukes from rats, demonstrates marked uniformity among worms within individual hosts. Possible effects of allometric growth are investigated by plotting each chosen dimension against body length for the two major groups of worms. Prominent changes are noted only in the relative size of testis in Skrjabinus from rats. Patterns of morphology are discussed in relation to host ecology and distribution. 相似文献
127.
128.
Neisseria gonorrhoeae was identified by the Phadebact gonococcus test, a rapid slide coagglutination technique, and the results obtained were compared with those obtained by conventional methods (Gram stain morphology, oxidase reaction, and carbohydrate utilization tests) for the confirmatory identification of gonococci. Of 308 clinical isolates examined, the coagglutination procedure correctly identified 97.8% of the isolates tested as N. gonorrhoeae and 93.9% of other bacteria as not N. gonorrhoeae. The coagglutination procedure also identified 29 laboratory strains correctly as not N. gonorrhoeae. The slide coagglutination test is easy to perform and offers a valuable alternative to other techniques for the confirmatory identification of N. gonorrhoeae. 相似文献
129.
The relationship of the oestrogen and progestin receptors in the abnormal uterus of the adult anovulatory rat. Effects of neonatal treatment with testosterone propionate or clomiphene citrate. 总被引:1,自引:1,他引:0
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The neonatal administration of testosterone propionate to Wistar rats resulted in anovulatory adults in persistent vaginal oestrus. Clomiphene citrate had a similar effect. In both groups of adults, hyperplasia of the uterine epithelium and occasional metaplasia was observed. The uterine nuclear and cytosol oestrogen and progestin receptors of these anovulatory rats were found to have affinities for their respective ligands similar to those of normal females. The nuclear oestrogen receptor comprised occupied and unoccupied components, as in normal females. The content of the nuclear oestrogen receptor was comparable with that of females in the late dioestrous or pro-oestrous phase. This content was higher in the clomiphene-treated group. Despite the relatively high nuclear oestrogen receptor content the content of progestin receptors, a putative index of the oestrogenic response, was lower in the treated rats than in normal adult females throughout the cycle. Administration of oestradiol to both treatment groups resulted in depletion of cytosol oestrogen receptor content 1 h later, which, however, was not reflected by an increase in the content of nuclear oestrogen receptors. There was no measurable increase in progesterone receptor content in treated rats after daily administration of oestrogen (5 microgram/rat) for 3 days. These changes in sex-hormone-receptor interactions involving an impairment of the normal oestrogenic response may be associated with the abnormal differentiation of the uterus in these sterile, anovulatory animals. 相似文献
130.
The surface disinfectant effect of glutaraldehyde in the gas-aerosol phase was investigated at different relative humidities and temperatures. At a gas-aerosol concentration of 15 to 20 mg/m3 and a relative humidity of about 80%, glutaraldehyde had a good disinfectant effect against both vegetative bacteria (decimal reduction time, less than 5 min) and bacterial spores (decimal reduction time, less than 45 min). In spite of its low volatility, glutaraldehyde was more effective than formaldehyde when the two substances were compared on an "added amount" basis. 相似文献